KR101077167B1 - Method for manufacturing non-oriented electrical steel sheets with improved magnetic property - Google Patents

Method for manufacturing non-oriented electrical steel sheets with improved magnetic property Download PDF

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KR101077167B1
KR101077167B1 KR1020030097496A KR20030097496A KR101077167B1 KR 101077167 B1 KR101077167 B1 KR 101077167B1 KR 1020030097496 A KR1020030097496 A KR 1020030097496A KR 20030097496 A KR20030097496 A KR 20030097496A KR 101077167 B1 KR101077167 B1 KR 101077167B1
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배병근
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주식회사 포스코
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1216—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the working step(s) being of interest
    • C21D8/1222—Hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1216—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the working step(s) being of interest
    • C21D8/1233—Cold rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1244—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest
    • C21D8/1261—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest following hot rolling
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/12—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties
    • C21D8/1244—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest
    • C21D8/1266—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of articles with special electromagnetic properties the heat treatment(s) being of interest between cold rolling steps
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/001—Ferrous alloys, e.g. steel alloys containing N
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/004—Very low carbon steels, i.e. having a carbon content of less than 0,01%
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium

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  • Chemical & Material Sciences (AREA)
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  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
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  • Manufacturing & Machinery (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Manufacturing Of Steel Electrode Plates (AREA)

Abstract

본 발명은 모터, 변압기 및 자기실드와 같은 전기기기의 철심으로 사용되는 철손이 낮고, 자속밀도가 높은 무방향성 전기강판의 제조방법에 관한 것으로, 중량%로 C:0.0010~0.0026%, Si:4.5% 이하(0%는 제외), Mn:0.5% 이하(0%는 제외), P:0.005% 이하(0%는 제외), S:0.005% 이하(0%는 제외), Al:0.2~1.5%, N:0.003% 이하(0%는 제외), O:0.003% 이하(0%는 제외)이며, C/P의 비가 0.2~6.0이고, C와 P의 합이 적어도 0.002% 이상으로 조성되며, 잔부 Fe 및 기타 불가피하게 첨가되는 불순물로 조성되는 슬라브를 1050℃이상 1200℃이하의 온도로 재가열후 열간압연하고,The present invention relates to a method of manufacturing a non-oriented electrical steel sheet having a low iron loss and high magnetic flux density used as an iron core of an electric device such as a motor, a transformer, and a magnetic shield. The weight ratio is C: 0.0010 to 0.0026% and Si: 4.5. % Or less (excluding 0%), Mn: 0.5% or less (excluding 0%), P: 0.005% or less (excluding 0%), S: 0.005% or less (excluding 0%), Al: 0.2 to 1.5 %, N: 0.003% or less (excluding 0%), O: 0.003% or less (excluding 0%), the ratio of C / P is 0.2-6.0, and the sum of C and P is formed at least 0.002%. , The remainder Fe and other unavoidable addition of the slab composed of the reheating to a temperature of more than 1050 ℃ 1200 ℃ hot rolled,

680℃ 이하의 온도로 권취, 열연판소둔 및 산세하며,Winding, hot rolled sheet annealing and pickling at a temperature of 680 ℃ or less,

1차 냉간압연후 830~1000℃온도로 중간소둔하고 2차 냉간압연하는 2회 냉간압연법으로 냉간압연하고,After the first cold rolling, it is cold-rolled by two cold rolling methods, intermediately annealed at 830 ~ 1000 ℃ and second cold rolling.

800~1070℃의 온도에서 10초 이상 300초 이내로 냉연판을 소둔하는 자성이 우수한 무방향성 전기강판의 제조방법을 제공한다.Provided is a method for producing a non-oriented electrical steel sheet having excellent magnetic properties for annealing the cold rolled sheet within 10 seconds to 300 seconds at a temperature of 800 ~ 1070 ℃.

본 발명에 따르면, 무방향성 전기강판 제조시 작용되는 불순물을 어느 정도 남겨두고도 그 자기적 특성을 향상시킬 수 있어 이들 불순물 제거에 소요되는 비용을 현저히 절감하고, 작업공수를 줄여 생산성 향상을 도모할 수 있다.According to the present invention, it is possible to improve the magnetic properties of the non-oriented electrical steel sheet to produce a certain amount of impurity, which can significantly reduce the cost of removing these impurities, and to improve the productivity by reducing the labor Can be.

무방향성, 전기강판, CORE LOSS, P, C, O, 자속밀도Non-oriented, Electrical Steel, CORE LOSS, P, C, O, Magnetic Flux Density

Description

자성이 우수한 무방향성 전기강판의 제조방법{Method for manufacturing non-oriented electrical steel sheets with improved magnetic property}Method for manufacturing non-oriented electrical steel sheets with improved magnetic property

본 발명은 모터, 변압기 및 자기실드와 같은 전기기기의 철심으로 사용되는 무방향성 전기강판의 제조방법에 관한 것으로서, 보다 상세하게는 철손이 낮고, 자속밀도가 높은 무방향성 전기강판의 제조방법에 관한 것이다.The present invention relates to a method for manufacturing non-oriented electrical steel sheet used as an iron core of an electric device such as a motor, a transformer and a magnetic shield, and more particularly, to a method for manufacturing a non-oriented electrical steel sheet having low iron loss and high magnetic flux density. will be.

무방향성 전기강판은 전기기기에서 전기적 에너지를 기계적 에너지로 바꾸어 주는데 필요한 중요한 부품으로서 에너지절감을 위해서는 그 자기적 특성 즉, 철손을 낮추고 자속밀도를 높이는 것이 필요하다.Non-oriented electrical steel sheet is an important component necessary for converting electrical energy into mechanical energy in electrical equipment. In order to reduce energy, it is necessary to lower magnetic properties, ie, iron loss and increase magnetic flux density.

철손은 에너지변환 과정에서 열로 변하여 사라지며, 자속밀도는 동력을 일으키는 힘으로 나타난다. 따라서, 자속밀도가 높으면 전기기기의 동손을 줄일 수 있어서 소형화가 가능하다.Iron loss turns into heat and disappears during the energy conversion process, and magnetic flux density appears as a power generating force. Therefore, when the magnetic flux density is high, the copper loss of an electric apparatus can be reduced and miniaturization is possible.

철손이 낮고 자속밀도가 높은 소재를 제조하려면 강의 불순물이 적은 청정강으로 제조하거나 특수원소를 첨가하기도 한다. 불순물원소는 C, S, P, N 및 기타 탄화물 및 질화물을 발생시키는 원소가 있다. In order to manufacture materials with low iron loss and high magnetic flux density, they may be made of clean steel with less impurities of steel or special elements may be added. Impurity elements include elements that generate C, S, P, N and other carbides and nitrides.                         

일본특허공보 특개평10-212555는 P를 첨가하고 있는데, 타발가공성을 향상시키기 때문으로 설명하고 있다. 또한, 일본특허공보 특개평10-18005는 기계적 특성향상을 위하여 P를 첨가하고 있다. 이와 같이 종전의 특허들은 기계적 특성을 향상시키기 위하여 P를 첨가하거나 함유시키고 있다.Japanese Patent Laid-Open No. Hei 10-212555 adds P, but it explains because it improves punching workability. In addition, Japanese Patent Laid-Open No. Hei 10-18005 adds P to improve mechanical properties. As such, previous patents add or contain P to improve mechanical properties.

한편, 대한민국 특허출원 2000-45785는 P가 0.001~0.005%인 범위를 특허청구범위로 하고 있으나 P가 낮은 이 범주에서 C 등 다른 원소와의 관계는 언급하지 않고 있다.On the other hand, Korean Patent Application 2000-45785 claims that the range of P is 0.001 ~ 0.005%, but does not mention the relationship with other elements such as C in this low P category.

Si, Mn 및 Al을 함유하는 무방향성 전기강판에서 불순물 원소로 알려진 원소인 C, P, S 및 N 등은 가능하다면 적게 함유되도록 하는 것이 자기적 특성을 향상 시키기 위하여 바람직하다. 그런데 이들 원소를 제거하기 위해서는 많은 제조비용을 들여야만 가능하게 된다.In the non-oriented electrical steel sheet containing Si, Mn and Al, elements such as C, P, S and N, which are known as impurity elements, are preferably contained as little as possible in order to improve magnetic properties. In order to remove these elements, however, a large manufacturing cost is required.

본 발명은 상술한 바와 같은 종래 기술상의 단점들을 감안하여 이를 더욱 개량 발전시키기 위하여 창출된 것으로, 무방향성 전기강판에서 불순물 원소로 알려진 C, P, S, N 등을 최대한 적게 함유하도록 어느 정도는 남겨 놓은 상태에서도 자기적 특성이 매우 우수한 그러한 형태의 무방향성 전기강판 및 그 제조방법을 제공하는 것에 본 발명의 목적이 있다.The present invention was created in order to further improve the development in view of the disadvantages of the prior art as described above, and to some extent left as little as possible to contain C, P, S, N, etc., known as impurity elements in non-oriented electrical steel sheet. It is an object of the present invention to provide such a non-oriented electrical steel sheet and a method of manufacturing the same having excellent magnetic properties even in a laid state.

본 발명은 상기한 기술적 과제를 달성하기 위하여, 중량%로 C:0.0010~0.0026%, Si:4.5% 이하(0%는 제외), Mn:0.5% 이하(0%는 제외), P:0.005% 이하(0%는 제외), S:0.005% 이하(0%는 제외), Al:0.2~1.5%, N:0.003% 이하(0%는 제외), O:0.003% 이하(0%는 제외)이며, C/P의 비가 0.2~6.0이고, C와 P의 합이 적어도 0.002% 이상으로 조성되며, 잔부 Fe 및 기타 불가피하게 첨가되는 불순물로 조성되는 슬라브를 1050℃이상 1200℃이하의 온도로 재가열후 열간압연하고,
680℃ 이하의 온도로 권취, 열연판소둔 및 산세하며,
1차 냉간압연후 830~1000℃온도로 중간소둔하고 2차 냉간압연하는 2회 냉간압연법으로 냉간압연하고,
800~1070℃의 온도에서 10초 이상 300초 이내로 냉연판을 소둔하는 자성이 우수한 무방향성 전기강판의 제조방법의 제조방법을 제공함에 그 특징이 있다.The present invention, in order to achieve the above technical problem, by weight% C: 0.0010 ~ 0.0026%, Si: 4.5% or less (excluding 0%), Mn: 0.5% or less (excluding 0%), P: 0.005% Or less (excluding 0%), S: 0.005% or less (excluding 0%), Al: 0.2 to 1.5%, N: 0.003% or less (excluding 0%), O: 0.003% or less (excluding 0%) The ratio of C / P is 0.2-6.0, the sum of C and P is at least 0.002%, and the reconstituted slab composed of the remaining Fe and other inevitable impurities is reheated to a temperature of 1050 ° C or more and 1200 ° C or less. After hot rolled,
Winding, hot rolled sheet annealing and pickling at a temperature of 680 ℃ or less,
After the first cold rolling, it is cold-rolled by two cold rolling methods, intermediately annealed at 830 ~ 1000 ℃ and second cold rolling.
It is characterized by providing a method for producing a non-oriented electrical steel sheet having excellent magnetic properties for annealing the cold rolled sheet within 10 seconds to 300 seconds at a temperature of 800 ~ 1070 ℃.

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특히, 본 발명을 구성하기 위해 각종의 조사와 검토를 행한 결과 금속재료 내부에는 결정립계가 존재하며, 이 결정립계안에는 불순물원소 특히 P와 C이 많은 것을 확인하였다. 이들 원소는 편석이 많이 발생되는 특성이 있으며, 결정립계 내부에는 어느 정도 이들 원소가 어느 정도 존재하는 것으로 판단되었다.In particular, as a result of various investigations and studies to constitute the present invention, grain boundaries exist within the metal material, and it is confirmed that there are many impurity elements, particularly P and C, in the grain boundaries. These elements have many segregation characteristics, and it was judged that these elements exist to some extent inside the grain boundary.

따라서, C와 P가 적정량 존재하여야 한다는 가정하에서 P와 C의 양을 변화시켜 실험한 결과, P가 0.005%이하로 존재하고 C량을 0.0010~0.0026%의 범위로 제어하고, C/P의 비를 적절하게 유지하여 C, P의 양을 일정하게 유지하면 철손이 낮고, 자속밀도는 높일 수 있는 것으로 조사되었다.Therefore, assuming that the appropriate amount of C and P should be present in the experiment by changing the amount of P and C, P is present in less than 0.005%, the amount of C is controlled in the range of 0.0010 ~ 0.0026%, C / P ratio Maintaining the proper amount of C and P to maintain the proper amount of iron loss was low, the magnetic flux density was investigated.

그리고, C와 P의 합이 적어도 0.002%이상이 요구되었다. 이때 O의 양이 많아지면 P저감의 효과가 떨어지기 때문에 0.0030%이하로 관리되어야 하는 것이 조사되었다.And the sum of C and P was required at least 0.002% or more. At this time, since the amount of O decreases, the effect of P reduction decreases.

결국, 본 발명의 조건으로 무방향성 전기강판을 제조할 때 철손을 낮추는 결정립의 크기가 크게 성장하며, 자화용이 방향인 <100> 방향이 많이 함유되는 (200)면의 집합조직이 잘 발달되어 자속밀도도 높아짐을 알 수 있었다.As a result, when the non-oriented electrical steel sheet is manufactured under the conditions of the present invention, the grain size lowering the iron loss is greatly increased, and the texture of the (200) plane containing a lot of <100> directions, which is easy for magnetization, is well developed and the magnetic flux. It can be seen that the density is also increased.

또한, 본 발명은 중량%로 C:0.001~0.0026%, Si:4.5%이하, Mn:0.5%이하, P:0.005%이하, S:0.005%이하, Al:0.2~1.5%, N:0.003%이하, O:0.0030%이하, 잔부 Fe 및 기타 불가피하게 첨가되는 불순물로 조성되는 강슬라브를 가열하여 열간압연하고 권취후 열연판을 소둔하고 중간소둔을 포함한 2회 냉간압연한후 냉간압연판을 최종소둔하는 자기적 특성이 우수한 무방향성 전기강판의 제조방법을 제공한다.In the present invention, C: 0.001% to 0.0026%, Si: 4.5% or less, Mn: 0.5% or less, P: 0.005% or less, S: 0.005% or less, Al: 0.2 to 1.5%, N: 0.003% Below, O: 0.0030% or less, hot rolled steel slab composed of balance Fe and other unavoidable impurities, hot rolled, annealing hot rolled sheet after winding, cold rolled sheet twice including intermediate annealing, and then cold rolled sheet Provided is a method for producing an oriented non-oriented electrical steel sheet excellent in annealing magnetic properties.

이하 본 발명에 따른 성분계의 수치한정에 대하여 설명한다. 아울러, 설명되지 아니하고 단지 %로 기재된 모든 표시는 중량%임을 전제로 한다.Hereinafter, numerical limitation of the component system according to the present invention will be described. In addition, it is assumed that all the indications which are not described and described only as a% are by weight.

[C:0.0010~0.0026%][C: 0.0010-0.0026%]

C는 최종제품에서 자기시효를 일으켜서 사용중 자기적 특성을 저하시키므로 일반적으로는 낮을 수록 자기적 특성에 바람직한 것으로 알려져 있다.C is known to be preferable for the magnetic properties, because the lower the magnetic properties during use to lower the magnetic properties during use in the final product.

그러나, 본 발명은 C가 0.0010%미만으로 과도하게 낮아도 자성이 저하되는 것, 특히 P가 0.005%이하로 낮아지면 자성이 현저히 저하되는 것을 확인하였다.However, the present invention confirmed that the magnetism is lowered even if C is excessively low, less than 0.0010%, in particular, when P is lowered below 0.005%, the magnetism is significantly reduced.

또한, C은 너무 높아도 자기적 특성이 저하되는 것을 확인하였다.Moreover, even if C was too high, it confirmed that a magnetic property fell.

그러므로, 제강의 성분제조단계에서 C은 0.0010~0.0026%의 범위로 한다.Therefore, C is in the range of 0.0010% to 0.0026% in the steelmaking component manufacturing step.

[Si:4.5%이하][Si: 4.5% or less]

Si는 비저항을 증가시켜서 철손중 와류손실을 낮추는 원소이지만 본 발명의 강에서는 냉간압연성을 고려하여 4.5%이하로 첨가한다.Si is an element that decreases the eddy current loss during iron loss by increasing the specific resistance, but in the steel of the present invention, it is added below 4.5% in consideration of cold rolling property.

[Mn:0.5%이하][Mn: 0.5% or less]

Mn은 비저항을 증가시키며, 집합조직을 향상시키므로 첨가하며, 너무 많아도 집합조직의 향상이 적으므로 0.5%이하로 첨가한다.Mn is added to increase the resistivity and improves the texture, and is added less than 0.5% because the improvement of the texture is too small.

[P:0.005%이하][P: 0.005% or less]

P는 편석원소이며, 불순물원소인 C을 0.0010~0.0026%로 함유시키고, P를 0.005%이하로 하며, C/P의 비가 0.2~6.0이 되게 함유되도록 함으로서 자기적 특성이 향상되었다. P가 0.005%를 초과하여 첨가되면 결정립성장이 억제되어 자성이 저하된다. 이때 C와 P의 합은 적어도 0.002%이상이 유지되어야 한다.P is a segregation element, and the impurity element C is contained in 0.0010 ~ 0.0026%, P is less than 0.005%, and the C / P ratio is contained so that 0.2 ~ 6.0, the magnetic properties are improved. When P is added exceeding 0.005%, grain growth is suppressed and magnetic property falls. The sum of C and P should be maintained at least 0.002%.

즉, 0.002% 이하인 경우에는 결정립계에 O나 N 등과 같은 원소들이 쉽게 이동하여 강 내부로 침투함으로써 내부 산화물이나 질화물이 과다하게 발생될 수 있고, 이들 질화물과 산화물은 결정립성장을 억제하여 자성을 저해하게 된다.That is, if the content is less than 0.002%, elements such as O and N easily move to the grain boundary and penetrate into the steel, causing excessive internal oxides or nitrides. These nitrides and oxides inhibit grain growth and inhibit magnetism. do.

또한, C/P이 비가 적어도 0.2 이상은 함유되어야 자성이 향상되며, 이것은 최대 P 함유량에 대한 C의 최소한의 함유비이고, 침입형원소 C를 적정수준으로 유지함으로써 결정립계에 O 나 N의 침입을 억제하는 효과가 있으며, 또한 C/P가 6 이하가 되어야 자성이 향상되며 이것은 최소한의 P에 대한 C의 최대 함량을 의미하고 이때 P는 가능하다면 0.0010% 이상이 필요하다.In addition, the C / P ratio is at least 0.2 or higher to increase the magnetism, which is the minimum content ratio of C to the maximum P content, and maintains the invasive element C at an appropriate level to prevent intrusion of O or N into the grain boundary. There is an inhibitory effect, and the magnetism is improved when C / P is 6 or less, which means the maximum content of C to the minimum P, where P is required to be 0.0010% or more.

[S:0.005%이하][S: 0.005% or less]

S는 미세한 석출물인 MnS를 형성하여 자기특성에 나쁜 영향을 미치므로 가능한한 낮게 함유되는 것이 유리하며, 본 발명에서는 0.005%이하로 함유토록 한다.S is advantageously contained as low as possible to form a fine precipitate MnS adversely affects the magnetic properties, in the present invention is to be contained less than 0.005%.

[Al:0.2~1.5%][Al: 0.2-1.5%]

Al은 비저항을 증가시켜 와류손실을 낮추는 역할을 하기 때문에 첨가하며, 0.2%미만으로 첨가되면 강내에 AlN의 미세한 석출물이 형성된다. 또한 1.5%를 초과하여 첨가시 첨가량에 비해 자성향상의 정도가 떨어진다. 따라서 Al은 0.2~1.5%로 첨가한다.Al is added because it decreases the eddy current loss by increasing the specific resistance, and when less than 0.2% is added, fine precipitates of AlN are formed in the steel. In addition, the degree of magnetic improvement is lower than the addition amount when added in excess of 1.5%. Therefore, Al is added in 0.2 ~ 1.5%.

[N:0.003%이하][N: 0.003% or less]

N은 미세하고 긴 AlN석출물을 형성함으로 가능한 적게 함유토록 하며, 본 발명에서는 0.003%이하로 한다.N is made to contain as little as possible by forming a fine and long AlN precipitate, in the present invention is less than 0.003%.

[O:0.003%이하][O: 0.003% or less]

O는 미세한 산화물 및 연성을 갖는 산화물을 만들며, 결정립계 편석원소가 낮게 함유될 경우 소재의 내부까지 침입하여 산화물을 쉽게 만들기 때문에 낮게 관리되어야 한다. 본 발명에서는 0.003%이하로 함으로서 낮은 P강의 첨가효과를 볼 수 있는 것으로 조사되었다.O produces fine oxides and ductile oxides, and if they contain low grain boundary segregation elements, they should be kept low because they easily penetrate into the interior of the material to make oxides. In the present invention, it was investigated that the effect of the addition of low P steel can be seen by less than 0.003%.

이하, 본 발명의 제조방법에 대하여 설명한다. Hereinafter, the manufacturing method of this invention is demonstrated.                     

상기와 같이 조성되는 강의 슬라브는 제강에서 용강으로 제조된후 연속주조공정에서 슬라브로 응고시키고, 열간압연을 하기 위하여 가열로로 장입하며, 가열시 슬라브의 온도는 1100~1200℃ 범위로 한다.The slab of the steel composition as described above is made of molten steel in the steelmaking and then solidified into the slab in the continuous casting process, charged into the heating furnace for hot rolling, the temperature of the slab during heating is in the range of 1100 ~ 1200 ℃.

1100℃ 보다 낮으면 압연시 압하부하가 너무 크게 되며, 1200℃ 보다 높게 가열하면, 불순물원소가 미세한 석출물로 석출되어 최종 제품의 결정립성장을 억제한다.If it is lower than 1100 ° C., the rolling load during rolling is too large, and if it is heated higher than 1200 ° C., impurity elements are precipitated as fine precipitates to suppress grain growth of the final product.

따라서, 재가열온도는 1050~1200℃의 범위로 한다.Therefore, reheating temperature shall be in the range of 1050-1200 degreeC.

열간압연후 열연판의 권취온도는 680℃ 이하에서 실시하고 공기중에서 코일상태로 또는 비산화성 분위기에서 냉각할 수 있고, 680℃가 넘으면 냉각시 소재의 내부산화로 자화가 곤란하여 자기적 특성이 나빠질 수 있다.After hot rolling, the coiling temperature of the hot rolled sheet is conducted at 680 ℃ or lower, and can be cooled in air in a coiled state or in a non-oxidizing atmosphere. If it exceeds 680 ℃, the magnetic properties are deteriorated due to the difficulty of magnetization due to internal oxidation of the material during cooling. Can be.

권취냉각된 열연판은 열연판소둔 생략하거나 또는 실시후 산세하고 냉간압연한다.The cold-rolled hot rolled sheet may be omitted or annealed and cold rolled after hot rolled sheet annealing.

냉간압연은 1차냉간압연후 중간소둔한 다음 2차냉간압연을 실시하는 2회냉연법을 쓸 수 있다.Cold rolling may be a two-stage cold rolling method where the first cold rolling is followed by an intermediate annealing followed by a second cold rolling.

중간소둔온도는 830~1000℃의 온도범위로 한다. 830℃ 보다 낮으면 충분한 재결정이 되지 않으며, 1000℃ 보다 높으면 과도한 입성장이 됨으로서 2차냉간압연후 재결정 소둔시 결정립성장이 부족하여 자성이 열화될 수 있다.The intermediate annealing temperature is in the range of 830 ~ 1000 ℃. If the temperature is lower than 830 ° C., sufficient recrystallization is not performed. If the temperature is higher than 1000 ° C., excessive grain growth may result in insufficient grain growth during recrystallization annealing after secondary cold rolling.

최종 냉간압연된 강판은 소둔하며, 소둔온도는 800℃ 이상 1070℃이하로 한다.The final cold rolled steel sheet is annealed, and the annealing temperature is 800 ° C or more and 1070 ° C or less.

소둔온도가 800℃ 보다 낮으면 결정립성장이 미흡하며, 1070℃ 보다 높으면 표면온도가 과다하게 높아서 판표면에 표면결함이 발생될 수 있으며, 자기적 특성도 나빠질 수 있기 때문이다.If the annealing temperature is lower than 800 ℃ grain growth is insufficient, if higher than 1070 ℃ the surface temperature is excessively high may cause surface defects on the surface of the plate and the magnetic properties may be worsened.

소둔시간은 10초이상 300초이내로 한다. 소둔시간은 적어도 10초 이상이 되어야 재결정이 충분히 일어날 수 있으며, 300초를 초과하면 내부산화가 일어날 수 있기 때문에 10초 이상 300초 이하로 한다.Annealing time is 10 seconds or more and 300 seconds or less. The annealing time should be at least 10 seconds or longer to sufficiently recrystallize. If it exceeds 300 seconds, internal oxidation may occur, so it is 10 seconds or more and 300 seconds or less.

이때 소둔분위기는 수소10%이상의 질소와의 건조한 비산화 혼합분위기로 할 수 있다.At this time, the annealing atmosphere may be a dry non-oxidizing mixed atmosphere with nitrogen of 10% or more of hydrogen.

수소가 10%미만이 되면 미세한 비금속개재물인 Al2O3, MnO 및 FeO가 강판의 표면직하에 발생되어 집합조직이 열화되어 자성이 나빠진다.When the hydrogen is less than 10%, fine non-metallic inclusions Al 2 O 3 , MnO and FeO are generated directly under the surface of the steel sheet, resulting in deterioration of the texture and deterioration of magnetic properties.

소둔판은 절연피막처리후 수요가로 출하된다. 절연피막은 유기질, 무기질 및 유무기복합피막으로 처리할 수도 있으며, 기타 절연이 가능한 피막제를 입힐 수 있다.Annealed plates are shipped at demand after insulation coating. Insulation coatings can be treated with organic, inorganic and organic-inorganic composite coatings, and can be coated with other insulating coatings.

이하, 실시예를 통하여 더욱 상세히 설명하기로 한다.Hereinafter, the embodiment will be described in more detail.

[실시예 1]Example 1

표 1과 같은 성분을 갖는 본 발명강 슬라브를 제조하고, 본 발명강과 성분조성이 비슷한 비교강 슬라브를 제조하였다.Inventive steel slabs having the components shown in Table 1 were prepared, and comparative steel slabs similar in composition to the inventive steel were prepared.

이어, 표 2와 같이 이들 슬라브를 재가열하고, 1.8mm로 열간압연후 650℃의 온도에서 권취하여 냉각하였다.Subsequently, these slabs were reheated as shown in Table 2, and hot-rolled to 1.8 mm, then wound up and cooled at a temperature of 650 ° C.

냉각된 열연판은 소둔온도 1050℃에서 3분간 소둔하고 산세한후 0.35mm 두께 로 1회 냉간압연하거나 1차 냉간압연후 중간소둔하고 2차 냉간압연 하였다.The cooled hot rolled sheet was annealed at an annealing temperature of 1050 ° C. for 3 minutes, pickled, and then cold rolled once to 0.35mm thickness, or intermediately annealed and cold rolled secondly after the first cold rolling.

냉연판소둔은 1070℃에서 소둔시간을 변화하여 실시되었으며, 소둔판은 절단후 자기적 특성 및 결정립크기가 조사되었다. 소둔분위기는 수소와 질소의 혼합분위기로 작업되었다.Cold-rolled annealing was carried out by varying the annealing time at 1070 ℃, the annealing plate was investigated the magnetic properties and grain size after cutting. The annealing atmosphere was operated with a mixed atmosphere of hydrogen and nitrogen.

실험결과, 본 발명의 성분범위와 제조조건에서 자기적 특성이 우수한 것으로 조사되었다.As a result, it was found that the magnetic properties were excellent in the component range and manufacturing conditions of the present invention.

강 종River bell CC SiSi MnMn PP SS AlAl NN OO C/PC / P 발명강aInventive Steel a 0.00100.0010 2.152.15 0.250.25 0.00120.0012 0.0010.001 0.380.38 0.00180.0018 0.00150.0015 0.80.8 발명강bInventive Steel b 0.00150.0015 2.942.94 0.260.26 0.00200.0020 0.0010.001 1.401.40 0.00170.0017 0.00120.0012 0.70.7 발명강cInvention steel c 0.00200.0020 2.922.92 0.270.27 0.00400.0040 0.0010.001 1.421.42 0.00160.0016 0.00100.0010 0.50.5 발명강dInvention 0.00120.0012 2.902.90 0.250.25 0.00500.0050 0.0020.002 1.431.43 0.00180.0018 0.00120.0012 0.20.2 발명강eInvention Steele 0.00260.0026 2.922.92 0.250.25 0.00060.0006 0.0020.002 1.101.10 0.00170.0017 0.00180.0018 4.34.3 비교강aComparative Steel a 0.00050.0005 2.932.93 0.260.26 0.01050.0105 0.0010.001 1.401.40 0.00170.0017 0.00160.0016 0.040.04 비교강bComparative Steel b 0.00350.0035 2.912.91 0.250.25 0.00800.0080 0.0010.001 1.421.42 0.00170.0017 0.00180.0018 0.40.4 비교강cComparative Steel c 0.00250.0025 2.922.92 0.250.25 0.00030.0003 0.0010.001 1.391.39 0.00180.0018 0.00170.0017 8.38.3 비교강dComparative strength d 0.00090.0009 2.922.92 0.250.25 0.00030.0003 0.0010.001 1.391.39 0.00180.0018 0.00400.0040 8.38.3

비교강a는 C가 과도하게 낮으며 C/P도 낮다.Comparative steel a has excessively low C and low C / P.

비교강b는 C와 P가 높으며, 비교강c는 C와 P가 관리범위를 만족하지만 C/P의 비가 너무 높으며, 비교강d는 O가 높고 C와 P의 합이 낮다.Comparative steel b has high C and P, comparative steel c has C and P satisfying the management range, but the ratio of C / P is too high, comparative steel d has high O and low sum of C and P.

아울러, 하기한 표 2에서와 같이, 비교재1은 재가열온도가 높았으며, 냉연판소둔시간이 짧았다. 비교재2는 재가열온도가 과도하게 낮아서 균질화가 되지 않았고 중간소둔 온도도 낮았으며, 비교재3과 비교재4는 성분비가 적합하지 않았다.In addition, as shown in Table 2 below, Comparative Material 1 had a high reheating temperature and a cold rolled sheet annealing time. Comparative material 2 was not homogenized due to excessively low reheating temperature, and the intermediate annealing temperature was also low. Comparative materials 3 and 4 were not suitable in component ratio.

시료번호Sample Number 재가열온도(℃)Reheating Temperature (℃) 중간소둔
온도(℃)Intermediate Annealing
Temperature (℃) 냉연판 소둔시간(초)Cold Rolled Annealing Time (sec) 철손
(W15/50)W/kgIron loss
(W 15/50 ) W / kg 자속밀도
(B50)TeslaMagnetic flux density
(B50) Tesla 결정립
크기(㎛)Crystal grain
Size (μm) 강 종River bell 발명재1Invention 1 11501150 미실시Not carried 5050 1.851.85 1.731.73 140140 발명강aInventive Steel a 발명재2Invention 2 11501150 미실시Not carried 5050 1.991.99 1.661.66 160160 발명강bInventive Steel b 발명재2Invention 2 11501150 930930 5050 1.901.90 1.651.65 170170 발명강bInventive Steel b 비교재1Comparative Material 1 12501250 미실시Not carried 55 2.382.38 1.641.64 135135 발명강bInventive Steel b 발명재3Invention 3 11201120 미실시Not carried 3030 1.891.89 1.691.69 160160 발명강cInvention steel c 발명재4Invention 4 11201120 미실시Not carried 6060 1.951.95 1.671.67 165165 발명강dInvention 발명재5Invention 5 11201120 미실시Not carried 200200 1.891.89 1.661.66 170170 발명강eInvention Steele 비교재2Comparative Material 2 10001000 700700 5050 2.312.31 1.641.64 120120 발명강aInventive Steel a 비교재3Comparative Material 3 11201120 900900 5050 2.122.12 1.641.64 145145 비교강bComparative Steel b 비교재4Comparative Material 4 11201120 900900 5050 2.452.45 1.631.63 125125 비교강cComparative Steel c 비교재5Comparative Material 5 11201120 900900 5050 2.522.52 1.641.64 105105 비교강dComparative strength d

W15/50 : 50Hz에서 1.5Tesla로 자화했을 때의 발생되는 손실W 15/50 : Loss generated when magnetizing to 1.5 Tesla at 50 Hz

B50 : 50Hz에서 5000A/m로 자기장을 부가했을 때의 유기되는 자속밀도B 50 : Induced magnetic flux density when a magnetic field is applied at 50 A at 5000 A / m

[실시예 2][Example 2]

중량%로 C:0.0023%, Si:3.2%, Mn:0.23%, P:0.002%, S:0.0005%, Al:1.24%, N:0.0017%, O:0.0017%, C/P=1.1이고, 잔부 Fe 및 기타 불순물로 조성되는 슬라브를 1130℃로 가열한후 1.9mm의 두께로 열간압연하고, 620℃온도로 권취냉각하였다.Weight% C: 0.0023%, Si: 3.2%, Mn: 0.23%, P: 0.002%, S: 0.0005%, Al: 1.24%, N: 0.0017%, O: 0.0017%, C / P = 1.1, The slab composed of the balance Fe and other impurities was heated to 1130 ° C., hot rolled to a thickness of 1.9 mm, and wound-cold to 620 ° C. temperature.

열연판은 1020℃에서 5분간 소둔하고 산세후 0.5mm로 1차냉연후 930℃에서 30초간 중간소둔후 2차냉간압연하고 산세후 0.20mm의 두께로 냉간압연하였다.The hot rolled sheet was annealed for 5 minutes at 1020 ℃, 0.5mm after pickling, the first cold rolling, and then intermediately annealed at 930 ℃ for 30 seconds, second cold rolling and cold rolling to a thickness of 0.20mm after pickling.

냉연판은 소둔온도 1050℃에서 1분간 소둔하였다.The cold rolled sheet was annealed at annealing temperature of 1050 ° C. for 1 minute.

소둔후 절단하고 자기적 특성을 측정한 결과 철손(W10/400)이 9.6W/kg이었고, 자속밀도(B50)는 1.66Tesla이었고, 결정립크기는 150㎛이었다.After annealing, cutting and magnetic properties were measured. The iron loss (W 10/400 ) was 9.6 W / kg, the magnetic flux density (B 50 ) was 1.66 Tesla, and the grain size was 150 μm.

[실시예 3]Example 3

중량%로 C:0.0012%, Si:0.98%, Mn:0.25%, P:0.004%, S:0.001%, Al:0.24%, N:0.0013%, O:0.0018%, C/P=0.3이고 잔부 Fe 및 기타 불순물로 조성되는 슬라브를 1150℃로 가열한후 2.2mm의 두께로 열간압연하고, 680℃온도로 권취후 냉각하였다.% By weight C: 0.0012%, Si: 0.98%, Mn: 0.25%, P: 0.004%, S: 0.001%, Al: 0.24%, N: 0.0013%, O: 0.0018%, C / P = 0.3 The slab composed of Fe and other impurities was heated to 1150 ° C., hot rolled to a thickness of 2.2 mm, wound up to 680 ° C., and cooled.

열연판은 950℃에서 4분간 소둔하고 산세후 0.5mm로 냉간압연후 950℃에서 30초간 소둔하였다.The hot rolled sheet was annealed at 950 ° C. for 4 minutes, cold rolled to 0.5 mm after pickling, and then annealed at 950 ° C. for 30 seconds.

소둔후 절단하고 자기적 특성을 측정한 결과 철손(W15/50)이 4.5W/kg이었고, 자속밀도(B50)는 1.75Tesla이었고, 결정립크기는 65㎛이었다.After annealing, cutting and magnetic properties were measured. The iron loss (W 15/50 ) was 4.5W / kg, the magnetic flux density (B 50 ) was 1.75 Tesla, and the grain size was 65 μm.

이들 실시예를 통해서, 본 발명의 조성범위와 제조방법을 통해 무방향성 전기강판 제조시 불순물을 일부 잔류시키면서도 우수한 자기적 특성을 갖도록 할 수 있음을 확인하였다.Through these examples, it was confirmed through the composition range and the manufacturing method of the present invention to have excellent magnetic properties while remaining some impurities in the production of non-oriented electrical steel sheet.

이상에서 상세히 설명한 바와 같이, 본 발명은 무방향성 전기강판 제조시 작용되는 불순물을 어느 정도 남겨두고도 그 자기적 특성을 향상시킬 수 있어 이들 불순물 제거에 소요되는 비용을 현저히 절감하고, 작업공수를 줄여 생산성 향상을 도모할 수 있다.As described in detail above, the present invention can improve the magnetic properties of the non-oriented electrical steel sheet production to some extent, leaving a significant reduction in the cost of removing these impurities, reducing the labor Productivity can be improved.

Claims (3)

삭제delete 삭제delete 중량%로 C:0.0010~0.0026%, Si:4.5% 이하(0%는 제외), Mn:0.5% 이하(0%는 제외), P:0.005% 이하(0%는 제외), S:0.005% 이하(0%는 제외), Al:0.2~1.5%, N:0.003% 이하(0%는 제외), O:0.003% 이하(0%는 제외)이며, C/P의 비가 0.2~6.0이고, C와 P의 합이 적어도 0.002% 이상으로 조성되며, 잔부 Fe 및 기타 불가피하게 첨가되는 불순물로 조성되는 슬라브를 1050℃이상 1200℃이하의 온도로 재가열후 열간압연하고,C: 0.0010 to 0.0026% by weight, Si: 4.5% or less (excluding 0%), Mn: 0.5% or less (excluding 0%), P: 0.005% or less (excluding 0%), S: 0.005% Or less (excluding 0%), Al: 0.2 to 1.5%, N: 0.003% or less (excluding 0%), O: 0.003% or less (excluding 0%), and C / P ratio is 0.2 to 6.0, The sum of C and P is at least 0.002%, and the slab composed of the balance Fe and other unavoidable impurities is reheated to a temperature of 1050 ° C or more and 1200 ° C or less, and then hot rolled. 680℃ 이하의 온도로 권취, 열연판소둔 및 산세하며,Winding, hot rolled sheet annealing and pickling at a temperature of 680 ℃ or less, 1차 냉간압연후 830~1000℃온도로 중간소둔하고 2차 냉간압연하는 2회 냉간압연법으로 냉간압연하고,After the first cold rolling, it is cold-rolled by two cold rolling methods, intermediately annealed at 830 ~ 1000 ℃ and second cold rolling. 800~1070℃의 온도에서 10초 이상 300초 이내로 냉연판을 소둔하는 것을 특징으로 하는 자성이 우수한 무방향성 전기강판의 제조방법.A method of manufacturing an excellent non-oriented electrical steel sheet, characterized in that the cold-rolled sheet annealing within 10 seconds to 300 seconds at a temperature of 800 ~ 1070 ℃.
KR1020030097496A 2003-12-26 2003-12-26 Method for manufacturing non-oriented electrical steel sheets with improved magnetic property KR101077167B1 (en)

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